Manufacturing quality requirements of bolted ball joint space frame components

Steel space frame structure is a relatively new form of building facility structure. In the production of steel space frame structure, we must pay attention to the quality. Unqualified quality will be an important problem for subsequent construction, and will even cause many safety risks. Therefore, the processing and production of steel structures starts from the source of quality. LFBJMB steel space frame structure company will introduce the production quality requirements of space frame  components from the following aspects.

1. Steel space frame structure rod processing. The rods are generally seamless steel pipes or welded steel pipes. Larger space frame structure have thousands of rods and various specifications. Therefore, when assembling unit parts, they must be positioned on special mold tires. When the steel pipe is welded with the cone or the sealing plate, the thermal deformation should be well controlled, and the phenomenon of undercut, slag inclusion and air hole during welding should be prevented. Non-destructive testing must be carried out for welds of tie rods with large and medium spans.
2. The bolt ball is the heart part of the steel space frame structure. Therefore, when machining the screw hole of the bolt ball, the thread accuracy should be 6-2G, the coaxiality of the through hole should be controlled at ±0.1mm, the angle error of the screw hole should be ±10°; the verticality between the screw hole and the plane should be controlled at ±0.05 about mm. During processing, thread plug gauges, angle gauges, vertical gauges and special measuring tools should be strictly tested at any time.
3. High-strength bolts are the main stress-bearing parts of the steelspace frame structure, and 40Cr or 45 steel should be used first, and the thread precision should be 6g-L. When processing the thread, use a sample knife to pick the buckle. In order to ensure the strength of the high-strength bolt, heat treatment is carried out after rough turning, and the overall salt bath quenching is carried out after finishing turning, and the hardness is randomly checked with a Rockwell hardness tester. For the thread form of bolt ball screw holes and high-strength bolts, it is recommended to use fine thread, which has the advantages of high connection strength, good self-locking performance, and not easy to loosen.
4. The connection between high-strength bolts and hexagonal sleeves depends on the diameter of the bolts. It is best not to use pins for bolts larger than M30. Our research has changed to a small top wire. The method is: mill a small keyhole on both sides of the bolt, drill two small screw holes on both sides of the matching hexagonal sleeve, and the small jacking screw slides in the keyway of the bolt through the screw hole on the hexagonal sleeve. This connection method is convenient for processing and installation, and is beneficial for force bearing.
5. The hexagonal sleeve is the connection between the high-strength bolt and the bolt ball. Its two end faces are combined with the steel ball screw hole plane and the cone (or sealing plate) platform respectively. The parallelism error of the two ends of the hexagonal sleeve must be strictly controlled within ±0.10mm, and the inner and outer planes of the cone (or sealing plate) must The above parallelism requirements are also met, so that the strength of the compression member can be ensured and installation gaps can be avoided.